Experimental results with an A6 relativistic magnetron

Summary Form only given, as follows. The A6 magnetron has been comprehensively studied in the long- and short-pulse regimes at voltages from 0.2 to 0.5 MV. For the first time, finite-length, cathode effects have been included in the frequency characteristics and the voltage-magnetic-field behavior of the A6 magnetron operating with a washer cathode. When the A6 oscillated in the pi mode, maximum power was emitted near the Hartree threshold condition. When it oscillated in the 2 pi mode, maximum power was emitted near the Hartree threshold condition if the cathode radius was effectively reduced as a result of the fringing fields produced by the axially short washer cathode. An empirical relationship has been established and used to extend two-dimensional resonance frequency calculations to account for some three-dimensional effects. The magnetron emitted slightly more power per vane when symmetrically loaded at two vanes (150 MW RSM at 0.5 MV) than when asymmetrically loaded at one vane (130 MW RMS). Slightly more power was generated in the 2 pi mode than in the pi mode.<>